package com.company;

import java.util.TreeMap;

class WordDictionary {
    private class Node{
        public boolean isWord;
        public TreeMap<Character , Node> next;

        public Node(boolean isWord){
            this.isWord = isWord ;
            next = new TreeMap<>();
        }

        public Node(){
            this(false);
        }
    }

    private Node root ;

    /** Initialize your data structure here. */
    public WordDictionary() {

        root = new Node();

    }

    /** Adds a word into the data structure. */
    public void addWord(String word) {

        Node cur = root;

        for(int i = 0 ; i < word.length() ; i++){
            char c = word.charAt(i);
            if(cur.next.get(c) == null)
                cur.next.put(c,new Node());
            cur = cur.next.get(c);
        }
        cur.isWord = true;
    }

    /** Returns if the word is in the data structure. A word could contain the dot character '.' to represent any one letter. */
    public boolean search(String word) {

        return match(root, word , 0);
    }

    private boolean match(Node node , String word,int index){

        if(index == word.length())  return node.isWord ;

        char c = word.charAt(index);

        if(c != '.'){
            if(node.next.get(c) == null)  return false;
            return match(node.next.get(c) , word,index + 1);
        }
        else{
           for(char nextChar : node.next.keySet())
               if(match(node.next.get(nextChar),word,index + 1))    return true ;
             return false ;
        }
    }
}